Histologic evaluation of a 12-year-old threaded hydroxyapatite-coated implant placed in conjunction with subantral augmentation procedure: a clinical report.

This clinical report presents a histologic evaluation of a threaded hydroxyapatite-coated root-form implant retrieved from the posterior maxillary area of a patient after being in function for 12 years. The implant had been placed in conjunction with subantral augmentation. Histologically, the portion of the implant that was examined under light microscopy appeared to be integrated with the surrounding bone; 74.3% of the surface of the implant had close bone apposition at the interface. The residual graft particles were present and in close proximity to the implant surface. These observations suggest that subantral augmentation procedure performed simultaneously with the placement of a hydroxyapatite-coated implant by using hydroxyapatite as a graft material may result in osseointegration between the implant and the surrounding bone that can be maintained under long-term function.